<!DOCTYPE html>
<html>
<meta charset="utf-8">
<script src="https://cdn.bootcss.com/angular.js/1.4.6/angular.min.js"></script>

<body>

<div ng-app="myApp" ng-controller="myCtrl">

    名:  <input type="text" ng-model="firstName"><br>
    姓:  <input type="text" ng-model="lastName"><br>
    <br>
    姓名: {{firstName + " " + lastName}}

</div>

<script>
    var app = angular.module('myApp', []);
    app.controller('myCtrl', function($scope) {
        $scope.firstName = "John";
        $scope.lastName = "Doe";
    });
</script>

</body>
</html>